METHOD OF DIFFERENTIATED DIAGNOSTICS OF DISSECTION WITH FORMATION OF INTRAMURAL HEMATOMA AND INTRA-ARTERIAL THROMBOSIS OF INTERNAL CAROTID ARTERIES Russian patent published in 2014 - IPC A61B5/55 

FIELD: medicine.

SUBSTANCE: invention can be used for differential diagnostics of occluding-stenosing affection of the internal carotid arteries, caused by dissection with the forming intramural hematoma (IMH) or intra-arterial thrombosis of the internal carotid artery. Magnetic-resonance tomography of the neck region is carried out in modes of time-of-flight magnetic-resonance angiography (TF MRA), T1f/s and T2f/s. A zone of changed MR signal from the intramural hematoma (IMH) or intra-arterial thrombus (IAT) of the internal carotid artery is identified on one tomographic section in the axial projection. Intensity of the changed MR signal from IMH or IAT of the internal carotid artery (I₁) and intensity of the MR signal from the pterygoid muscle from the same side (I₂), are determined; an index of contrast (C) in the zone of the changed MR signal from the internal carotid artery in comparison with the MR signal from the pterygoid muscle from the same side is calculated on their basis by formula: C=(I₁-I₂)/I₂. If the duration of clinical IMH or IAT symptoms is from 1 to 3 days, when the increased MR signal in the T2f/s mode with the contrast index in the range 3.666<C<4.180 is obtained, intra-arterial thrombosis is diagnosed, and if the decreased MR signal in the T2f/s mode with the negative contrast index in the range 0.070<C<-0.099 is obtained, dissection with the forming intramural hematoma is diagnosed. In the terms from 4 days to two months in the TF MRA mode with values of the contrast index in the range -0.006<C<0.13, and in the T1f/s mode in the range 0.3<C<1.89, intra-arterial thrombosis is diagnosed, in case of the increased MR signal in the TF MRA mode in the range 0.3<C<2.15, and in the T1 f/s mode in the range 0.98<C<3.23, dissection with the forming intramural hematoma is diagnosed.

EFFECT: method ensures accuracy of differential diagnostics of the said processes and unambiguous choice of a particular mode of magnetic-resonance angiography for diagnostics of IMH or intra-arterial thrombus in terms from the most acute period to two months.

2 tbl, 3 dwg, 2 ex